Nondestructive imaging detectors for energetic particle beams

Abstract

This paper describes the design and discusses initial experimental results produced from a nondestructive, position sensitive particle beam detector. The detector measures the spatial and intensity distribution of a particle beam by determining the position and intensity of secondary electrons or ions produced by particle beam interactions with thin foils ( ∼ 10 μg/cm 2) or wire grids. These secondary charged particles are focused onto an imaging detector using stigmatic ion optics which provide a high degree of correlation between the position of the incident particle beam at the foil and the position of secondary ions at the image sensor. The imaging detector is nonintrusive to the particle beam flux since most of the incident beam passes through the thin foil or around the wire mesh. This detector can monitor particle beam intensities ranging from tens of microamperes down to several hundred particles per second. Image resolution on the order of 5 μ is observed for particle beams having diameters on the order of several millimeters.